Showing papers by "Veterans Health Administration published in 1979"
TL;DR: Review of 35 cases of campylobacter enteritis identified a typical clinical syndrome with acute onset of diarrhea, abdominal pain, fever, and constitutional symptoms, and Epidemiologic investigation strongly suggested an external source for the infection in 22 of 35 patients.
Abstract: Campylobacter fetus subspecies (ssp.) jejuni has been recently recognized to cause diarrheal disease in man. To assess its importance as an enteric pathogen, we prospectively studied 514 patients with diarrhea. Campylobacter fetus ssp. jejuni was isolated from the feces of 26 patients (5%) and seven of 11 of their symptomatic household contacts. This organism was isolated from the feces of only one of 18 asymptomatic household contacts and not at all from 157 other healthy persons. Seventeen of 20 patients from whom C. fetus ssp. jejuni was isolated from fecal culture showed at least a fourfold rise in specific IgG titers. Review of 35 cases of campylobacter enteritis identified a typical clinical syndrome with acute onset of diarrhea, abdominal pain, fever, and constitutional symptoms. Stool examination revealed blood in 60% and polymorphonuclear leukocytes in 78% of patients. Epidemiologic investigation strongly suggested an external source for the infection in 22 of 35 patients.
551 citations
TL;DR: The glutamine synthetase content correlated well with sites of suspected glutamergic activity in keeping with the view of a critical role of astrocytes in the regulation of the putative neurotransmitter glutamic acid.
Abstract: The results of a light microscopic immunohistochemical study of glutamine synthetase in rat nervous system are presented. In all sites studied the enzyme was confined to astrocytes. Except for trace amounts in ependymal cells, the enzyme was not observed in other cells of the nervous system including neurons, choroid plexus, third ventricular tanycytes, subependymal cells and mesodermally-derived elements. The intensity of astrocyte staining varied in different regions with the greatest degree noted in the hippocampus and cerebellar cortex while the least was noted in brain stem, deep cerebellar nuclei and spinal cord. The glutamine synthetase content correlated well with sites of suspected glutamergic activity in keeping with the view of a critical role of astrocytes in the regulation of the putative neurotransmitter glutamic acid.
360 citations
TL;DR: It is concluded that exercise cross-sectional echocardiography is technically difficult but feasible and the mechanical consequences of exercise-induced regional myocardial ischemia can be detected noninvasively by real-time, two-dimensional, cross-sections echOCardiography.
Abstract: We performed cross-sectional echocardiograms at rest, during supine bicycle exercise, and after sublingual nitroglycerin administration in 28 patients suspected of having ischemic heart disease. Technically adequate exercise cross-sectional echocardiograms were obtained in 20 patients (71%). Ten patients had new areas of reversible segmental dysynergy, and all 10 had significant stenoses of coronary arteries supplying areas of the heart corresponding to the location of reversible dysynergy. Six of these 10 patients also underwent exercise thallium-201 perfusion scanning, and all six had reversible perfusion defects in the area that demonstrated reversible dysynergy on exercise cross-sectional echocardiography. At least two of the remaining 10 patients who did not have reversible segmental dysynergy on exercise cross-sectional echocardiography probably experienced myocardial ischemia that we did not detect. We conclude that exercise cross-sectional echocardiography is technically difficult but feasible. The mechanical consequences of exercise-induced regional myocardial ischemia can be detected noninvasively by real-time, two-dimensional, cross-sectional echocardiography.
241 citations
TL;DR: It is suggested that mineralization of the stylohyoid complex is not uncommon and probably only rarely causes symptoms and was observed more commonly in patients 50 to 59 years of age.
193 citations
TL;DR: Because chemotactic peptides from C5 can be generated by a variety of enzymes, this work suggests a relationship between complement, coagulation, and inflammation.
Abstract: Complement-activated human plasma causes generation of tissue factor in human leukocytes. This phenomenon appears to be related to the fifth component of complement (C5) as demonstrated by the use of C5 deficient-plasma and suppression of activity with antibody to C5. Isolation of the chemotactic factor from activated serum or trypsinization of purified C5 reproduces the phenomenon. These data provide evidence for a direct link between complement products and activation of the coagulation system. Because chemotactic peptides from C5 can be generated by a variety of enzymes, our findings suggest a relationship between complement, coagulation, and inflammation.
178 citations
TL;DR: It is reported that the mean concentration of circulating parathyroid hormone measured by this assay increases with age and that this age-related increase in hormone level is associated with decreases in mean serum ionized calcium and mean serum phosphorus.
Abstract: IN the process of conducting studies to characterize the effects of age on bone mass and the skeleton in adult human subjects, we measured serum immunoreactive parathyroid hormone by a radioimmunoassay that is specific for the biologically inactive carboxylterminal portion of the hormone. We now report that the mean concentration of circulating parathyroid hormone measured by this assay increases with age and that this age-related increase in hormone level is associated with decreases in mean serum ionized calcium and mean serum phosphorus. Methods Normal subjects who ranged in age from 21 to 89 years were studied. The 75 men and . . .
171 citations
TL;DR: A requirement for Na+ in FMLP-induced O2- generation is supported and a Na+ influx may underlie the nature of this requirement and the data are consistent with the hypothesis that a Na- influx may precede the Ca2+ influx in the FMLp-induced activation sequence.
Abstract: Human peripheral neutrophils generated superoxide radicals as assessed by ferricytochrome C reduction in response to activation by the synthetic chemotactic factor, N-formyl-methionyl-leucyl-phenylalanine. Superoxide generation was inhibited by 2-deoxy-D-glucose (ID50 4 X 10(-5)M), 2-iodoacetate (ID50 5 X 10(-5)M), and N-ethyl-maleimide (ID50 5 X 10(-6)M), suggesting a dependence on anaerobic glycolysis and sulfhydryl groups. Ouabain, microtubule-disrupting agents, inhibitors of respiration, oxidative phosphorylation, and protein and nucleic acid synthesis were without appreciable effects. Indomethacin (ID50 1 X 10(-4)M), ibuprofen (ID50 9 X 10(-4)M, and phenylbutazone (ID50 1 X 10(-5)M) all caused dose-dependent inhibition of superoxide generation at concentrations approximating those plasma and tissue levels obtained in human beings at therapeutic doses. Acetylsalicylic acid (125-500) microgram/ml) and aurothioglucose (10(-3)-10(-6)M) were without appreciable effects. Superoxide generation was inhibited only by relatively high concentrations of hydrocortisone (ID50 greater than 10(-3)M). Because superoxide radicals have been implicated in the pathogenesis of tissue injury in several forms of inflammation and arthritis in vivo, these studies suggest that the production of a potential cytotoxic factor may be subject to pharmacologic manipulation and that at least some of the antiphlogistic effects of the nonsteroidal antiinflammatory agents may be mediated through effects on superoxide production.
170 citations
TL;DR: Postoperative treatment either with aspirin and dipyridamole or with warfarin failed to improve the patency of the grafts and no statistically significant differences were found in various clinical, hemodynamic and angios.
Abstract: Fifty patients who underwent aortocoronary saphenous-vein bypass-graft surgery were randomly assigned to one of three groups to determine the effects of antiplatelet or anticoagulant therapy on graft patency. Twenty-four patients served as controls; 13 patients received aspirin (325 mg three times a day) and dipyridamole (75 mg three times a day); and 13 patients received closely regulated warfarin therapy. Medications were begun on the third post-operative day. Six months after surgery, all patients underwent coronary angiography to assess graft patency. There were no statistically significant differences between groups in various clinical, hemodynamic and angios, 27 of 33 grafts (82 per cent) with aspirin and dipyridamole and 29 of 37 grafts (78 per cent) with warfarin (P less than 0.5), all patients had at least one patent graft. Postoperative treatment either with aspirin and dipyridamole or with warfarin failed to improve the patency of the grafts.
157 citations
TL;DR: The direct participation of Ro-anti-Ro immune complexes in the progressive renal disease and may underlie the association seen here between the decreasing serum titers of antibodies to Ro and the clinical deterioration in these two cases.
Abstract: Two patients with systemic lupus erythematosus were studied whose sera contained precipitating antibodies to a soluble cytoplasmic antigen, termed Ro. A reduction in the amount of these antibodies in each case was accompanied by a deterioration in the clinical status with the development of nephritis leading to death. Acid elution of gamma globulin was performed from homogenates of the renal cortex, and in both instances antibodies to Ro were demonstrated in the eluates by double immunodiffusion. The titer of these antibodies was measured in both sera and eluates, and specific enrichment of anti-Ro in the eluates was demonstrated in both patients. This strongly suggests the direct participation of Ro-anti-Ro immune complexes in the progressive renal disease and may underlie the association seen here between the decreasing serum titers of antibodies to Ro and the clinical deterioration in these two cases.
124 citations
117 citations
TL;DR: Patients with small-cell bronchogenic carcinoma who received intensive remission-induction chemotherapy randomly received either thymosin fraction V, 60 mg/sq m or 20 mg/ sq m twice weekly, or no thymOSin treatment during the initial six weeks of chemotherapy, had significantly prolonged survival times relative to the other treatment groups.
Abstract: Patients with small-cell bronchogenic carcinoma who received intensive remission-induction chemotherapy randomly received either thymosin fraction V, 60 mg/sq m or 20 mg/sq m twice weekly, or no thymosin treatment during the initial six weeks of chemotherapy. Chemotherapy was then continued for two years. Thymosin administration did not increase the complete response rate. Patients receiving thymosin, 60 mg/sq m, had significantly prolonged survival times relative to the other treatment groups. This benefit was due to prolonged relapse-free survival in complete responders to treatment. The mechanism by which thymosin increased survival duration is unclear but may relate to restoration of immune deficits due to disease or treatment.
TL;DR: Results verify the utility of this medium and support the concept that C. difficile accounts for the cytotoxin found in stools in nearly all cases.
Abstract: Stools from patients with antibiotic-associated diarrhea or colitis were cultured to detect the presence of Clostridium difficile. All specimens contained a cytotoxin which was neutralized by Clostridium sordellii antitoxin. Initial testing employed several methods with comparative merits in recovering this organism. These included the use of nonselective media, antibiotic-incorporated media, alcohol shock, and paracresol-containing broth. Optimal results were achieved with primary plating of serial dilutions onto a selective agar containing cycloserine and cefoxitin. This technique was then employed in a large number of specimens. The overall results showed that C. difficile was recovered in specimens from 71 of 73 patients. All isolates of C. difficile produced a cytotoxin which was neutralized by C. sordellii antitoxin in vitro. These results verify the utility of this medium and support the concept that C. difficile accounts for the cytotoxin found in stools in nearly all cases.
Journal Article•
TL;DR: The presence of immunoregulatory A/P cells in the PBMN cells of chronically infected schistosomiasis mansoni patients have the capability to suppress lymphocyte blastogenesis induced by the antigenic preparations derived from adult worms and the infectious, cercarial, larval stage of the parasite Schistosoma mansoni.
Abstract: Peripheral blood mononuclear cells (PBMN) from chronically infected schistosomiasis mansoni patients responded poorly in vitro to a soluble schistosomal egg antigen preparation (SEA) and moderately well to either soluble worm (SWAP) or soluble cercarial (CAP) antigenic preparations. The responses induced by SWAP or CAP were dramatically increased, in 84 and 92%, respectively, of the 24 chronically infected patients tested, upon removal of adherent/phagocytic (A/P) cells from the original cell populations. In contrast, removal of A/P cells from the PBMN of treated patients, transiently infected patients, and uninfected control subjects did not result in enhanced reactivity to these antigens. Overall, SEA-induced responsiveness of chronically infected patients9 cells remained low in spite of A/P cell removal. Lymphocyte transformation induced by phytohemagglutinin-P and Candida albicans extract was not significantly altered by removal of A/P cells in any of the groups tested. The expression of another regulatory system concerned with a nonspecific suppressive influence exerted by SEA was also unaffected by the presence or absence of A/P cells. The previously reported, in vitro , schistosome antigen-specific, serosuppression mediated by sera from most chronically infected patients was effective in the presence or absence of A/P cells. However, serosuppression and A/P cells combined to exert maximum suppression of both the SWAP- and CAP-induced responses of chronically infected patients9 cells. The enhanced responses observed after A/P cell depletion represented actual increases in blastogenesis, as determined morphologically, as well as increased incorporation of tritiated thymidine. These studies have demonstrated the presence of immunoregulatory A/P cells in the PBMN cells of chronically infected schistosomiasis mansoni patients which have the capability to suppress lymphocyte blastogenesis induced by the antigenic preparations derived from adult worms and the infectious, cercarial, larval stage of the parasite Schistosoma mansoni .
TL;DR: From competition assays, the receptor possessed specificity for estradiol and the estrogen-like compound diethylstilbestrol, but not for progesterone, testosterone, triamcinolone or cortisol, Dihydrotestosterone was shown to bind slightly and only at high concentrations.
TL;DR: The neuropsychological performance of alcoholic men in their late 30s, some of whom has been abstinent for 3 weeks and others for 18 months, was compared with that of a group of men who drank occasionally to suggest that a simple "dose-effect" relationship between alcohol use and cognitive decline cannot be assumed.
Abstract: The neuropsychological performance of alcoholic men in their late 30s (mean age, 37 years), some of whom has been abstinent for 3 weeks and others for 18 months, was compared with that of a group of men who drank occasionally. There were no differences between the alcoholic groups and the comparison group that could not be attributed to normal aging. The number of years of alcoholism or estimated lifetime alcohol use, dietary adequacy, and medical or blackout history did not relate to neuropsychological impairment. The authors suggest that a simple "dose-effect" relationship between alcohol use and cognitive decline cannot be assumed.
TL;DR: The data suggest that a number of factors can cause a release of toxin from C. difficile into the surrounding medium.
Abstract: A method for the continuous culture of Clostridium difficile has been described. It has been shown that subjecting continuous cultures of this microorganism to environmental stress results in increased levels of toxin in culture medium. Factors found to cause this release include alteration of the Eh from --360 to +100 mV or increasing the temperature from 37 to 45 degrees C. The increased toxin levels were not associated with a change in viable cell density or the numbers of spores present. Additional studies have shown that subinhibitory concentrations of vancomycin and penicillin, but not clindamycin, also cause an increase in toxin levels during continuous culture. The increase in supernatant toxin levels occurs concomitant with a decrease in sonicated cell extract toxin levels. The data suggest that a number of factors can cause a release of toxin from C. difficile into the surrounding medium.
Journal Article•
TL;DR: It is demonstrated that Aspergillus antigenemia occurs during the course of experimental disseminated aspergillosis and illustrates the potential of an AsperGillus antigen RIA for sensitive, specific immunodiagnosis of human infections.
TL;DR: The records of 82 patients with penetrating gunshot wounds of the head seen during a 2-year period (1973 through 1975) were reviewed and all patients had a thorough neurologic evaluation and diagnostic roentgenographic studies within 5 hours of injury.
Abstract: The records of 82 patients with penetrating gunshot wounds of the head seen during a 2-year period (1973 through 1975) were reviewed. All patients had a thorough neurologic evaluation and diagnostic roentgenographic studies within 5 hours of injury. The state of consciousness, which could be assesse
TL;DR: In this paper, a new approach to the study of the "burst" of oxygen consumption in stimulated human platelets is described, following addition of collagen, thrombin, or arachidonic acid to washed platelets, O2 consumption and aggregation were measured concurrently.
TL;DR: Fever patterns were studied prospectively and retrospectively to suggest that, with the possible exception of sustained fever in Gram-negative pneumonia or CNS damage, the fever pattern is not likely to be helpful diagnostically.
Abstract: Fever patterns were studied prospectively in 200 consecutive patients referred for infectious disease consultation and retrospectively in 204 patients with selected infectious or noninfectious diseases. Most patients had remittent or intermittent fever, which, when due to infection, usually followed diurnal variation. Hectic fever occurred less commonly but was observed in patients with all categories of infectious or noninfectious diseases. Although hectic fevers were seen more frequently in patients who had documented bacteremia, there were many nonbacteremic subjects who had this pattern and others without this pattern who had bacteremia. Sustained fever nearly always occurred in patients with Gram-negative pneumonia or CNS damage, although some patients with these diseases had other patterns as well. Our data suggest that, with the possible exception of sustained fever in Gram-negative pneumonia or CNS damage, the fever pattern is not likely to be helpful diagnostically.
TL;DR: It is inferred that betaIndianapolis is rapidly precipitated from the soluble cell phase to the membrane, where it is catabolized, and may be responsible for the severe clinical manifestations associated with this variant.
Abstract: Hemoglobin (Hb) Indianapolis is an extremely labile beta-chain variant, present in such small amounts that it was undetectable by usual techniques. Clinically, it produces the phenotype of severe beta-thalassemia. Biosynthetic studies showed a beta:alpha ratio of 0.5 in reticulocytes and about 1.0 in marrow after a 1-h incubation. These results, similar to those seen in typical heterozygous beta-thalassemia, suggested that betaIndianapolis was destroyed so rapidly that its net synthesis was essentially zero. To examine the kinetics of globin synthesis, reticulocyte incubations of 1.25--20 min were performed with [3H]leucine. The betaIndianapolis:beta A ratio at 1.25 min was 0.80 suggesting that beta Indianapolis was synthesized at a near normal rate. At 20 min, this ratio was 0.46 reflecting rapid turnover of beta Indianapolis. The erythrocyte ghosts from these incubations contained only betaIndianapolis and alpha-chains, and the proportion of betaIndianapolis decreased with time, indicating loss of betaIndianapolis. Pulse-chase studies showed little change in beta A:alpha ratio and decreasing betaIndianapolis:alpha and betaIndianapolis:beta A with time. The half-life of betaIndianapolis in the soluble hemoglobin was approximately equal to 7 min. There was also rapid loss of beta Indianapolis from the erythrocyte membrane. From these results, it may be inferred that betaIndianapolis is rapidly precipitated from the soluble cell phase to the membrane, where it is catabolized. Heterozygotes for beta 0-thalassemia usually have minimal hematologic abnormalities, whereas heterozygotes with betaIndianapolis, having a similar net content of beta-chain, have severe disease. The extremely rapid precipitation and catabolism of betaIndianapolis and the resulting excess of alpha-chains, both causing membrane damage, may be responsible for the severe clinical manifestations associated with this variant. It seems likely that other, similar disturbances in the primary sequence of globin polypeptide chains may produce clinical findings similar to those seen with hemoglobin Indianapolis and thus produce the phenotype of severe beta-thalassemia.
TL;DR: The drug is effective when given intravenously or by the oral route in controlling ventricular arrhythmias especially following acute myocardial infarction but the side effects are greater during parenteral administration as discussed by the authors.
Abstract: Mexiletine is a new local anaesthetic antiarrhythmic agent whose chemical structure and electrophysiological properties closely resemble those of lignocaine although its anticonvulsant and pharmacokinetic properties differ from that drug. Unlike lignocaine (lidocaine) it is active following oral administration with a plasma half-life varying between 8 and 20 hours so that it can be administered twice or three times daily to sustain therapeutic plasma levels. The drug is effective when given intravenously or by the oral route in controlling ventricular arrhythmias especially following acute myocardial infarction but the side effects are greater during parenteral administration. Side effects during chronic oral therapy with mexiletine have not posed a serious problem. Mexiletine has the pharmacodynamic and pharmacokinetic properties of an agent suitable for the chronic oral prophylaxis of serious ventricular arrhythmias in patients with ischaemic heart disease.
TL;DR: Because both dogs and patients were probably infected at the same place, canine blastomycosis may be an important epidemiologic marker, alerting physicians to the possible presence of concomitant blastomyCosis in humans.
Abstract: Blastomycosis occurred in six patients in five households. In each instance one or more dogs living with the family or living near the family also developed blastomycosis. The recognition ...
TL;DR: Specific, high affinity estrogen receptor has been shown to be present in the rat thymus and Autoradiographic studies show that the radioactive label is concentrated in single cells which may be of the reticulo-epithelial variety.
TL;DR: It is suggested that cutaneous vasculitis, including acute necrotizing (leukocytoclastic) Vasculitis and some forms of lymphocytic vasculopathy, and perhaps some diseases characterized by a lymphocytics perivascular infiltrate, may represent cutaneous expressions of immune complex disease.
Abstract: To investigate the pathogeneic significance of immune complexes in cutaneous vasculitis, 107 patients with various forms of cutaneous vasculitis, including 59 patients with necrotizing (leukocytoclastic) vasculitis (group 1), and 48 patients with lymphocytic vasculitis, or a predominately lymphocytic perivascular infiltrate (group 2), were studied. Immunoglobulins or complement components in cutaneous blood vessels were detected by direct immunofluorescence in high frequency in both groups (91 and 88%, respectively). Using two radioassays for circulating immune complexes, Clq or monoclonal rheumatoid factor (mRF) reactive material was detected in 68% of the patients with necrotizing vasculitis but only 44% of the patients in the lymphocytic-perivascular group. The mRF radioassay was elevated in 58% of the first group of patients and 41% of the patients in group 2, although Clq binding activity was increased in 54% of the patients with necrotizing vasculitis but only in 9% of the patients with a lymphocytic vasculitis or lymphocytic perivascular infiltrate. By using both sucrose density gradient ultracentrifugation and Sepharose 6B gel filtration, the Clq and mRF reactive material detected in some patients with necrotizing vasculitis eluted in high molecular weight fractions that were also anticomplementary. In one patient with necrotizing vasculitis and hepatitis B antigenemia, these heavy molecular weight Clq and mRF reactive fractions contained a two- to three-fold increase in hepatitis B surface antigen when compared with lighter molecular weight fractions. Heavy and light molecular weight mRF reactive material could be detected in selected patients in the lymphocytic-perivascular group as well as in the necrotizing vasculitis group. These studies suggest that cutaneous vasculitis, including acute necrotizing (leukocytoclastic) vasculitis and some forms of lymphocytic vasculitis, and perhaps some diseases characterized by a lymphocytic perivascular infiltrate, may represent cutaneous expressions of immune complex disease.
Journal Article•
TL;DR: Findings indicate that most perimandibular space infections involve a polymicrobial flora in which anaerobic bacteria are the dominant isolates, and antimicrobial decisions should account for these observations.
Abstract: The bacteriology of 21 perimandibular clised-space infections was studied prospectively using optimal bacteriological techniques to collect, transport, and process specimens. There was an average of six microbial species per specimen, including approximately four anaerobes and two aerobes. The predominant aerobes were alpha-hemolytic and non-hemolytic streptococci; the predominant anaerobes were peptostreptococci, Bacteroides melaninogenicus, and Fusobacterium nucleatum. These findings indicate that most perimandibular space infections involve a polymicrobial flora in which anaerobic bacteria are the dominant isolates. Antimicrobial decisions should account for these observations, particularly in cases where cultural data are not available or when anaerobic cultures are not performed with optimal techniques.
TL;DR: The single transverse horizontal axis as a fact in articulating instruments and as a theory in the human craniomandibular complex and the terms "transverse horizontal mandibular axis" and "intercondylar axis" should not be confused or used as synonyms.
Abstract: 1. Within the limits of accuracy imposed by individual operators, equipment, and patient variations, a single transverse horizontal axis can usually appear to be located. 2. Location of a kinematic axis is worthwhile clinical procedure to transfer an arc of rotation in the sagittal plane from the patient to an articulator. 3. Past experiments have been useful, but none have proved or disproved the presence of colinear or noncolinear condyle arcs. Only the arc of the rigid clutch and its associated mechanism is located. Such an apparent arc may result from the resolution of compound condylar movements. 4. The right angle-nonright angle concept is misleading and generally is not applicable to clinical procedures. 5. The anatomic asymmetries of the axis transfer procedure may result in cast dislocations that may produce undesirable alterations in esthetic tooth positions. 6. The single transverse horizontal axis as a fact in articulating instruments and as a theory in the human craniomandibular complex. 7. The terms "transverse horizontal mandibular axis" and "intercondylar axis" should not be confused or used as synonyms. The term "transverse horizontal mandibular axis" ("hinge axis") should be used instead of "condylar" or "intercondylar" axis.
TL;DR: Harman (1-methyl-β-carboline) was the only β- carboline unequivocally identified in platelet samples with these techniques, and may be of importance in the metabolism and the pharmacological-toxicological actions of alcohol.
Journal Article•
TL;DR: Cognitive impairment was found to be more highly related to clinical ratings of patients' level of functioning on the treatment ward, to the successful completion of inpatient treatment, and to fewer relapses, longer abstinence periods, and lower rates of alcohol consumption at a 1 year follow-up than were lower BAQ scores.
Abstract: The relationship of cognitive impairment to treatment outcome in a sample of male alcoholics (N = 30) was explored. The Brain-Age Quotient (BAQ), an index of problem solving and adaptive abilities based on a battery of neuropsychological tests, was used as the summary measure of cognitive impairment. High BAQ scores were found to be more highly related to clinical ratings of patients' level of functioning on the treatment ward, to the successful completion of inpatient treatment, and to fewer relapses, longer abstinence periods, and lower rates of alcohol consumption at a 1 year follow-up than were lower BAQ scores. The implications of these findings with regard to appropriate treatment planning are discussed.
TL;DR: Changes in the upstream and downstream pressure drops, as evaluated by outflow occlusion, reflect changes in the lobar arterial and venous resistances, using the low-viscosity bolus technique.
Abstract: We perfused the left lower lobe of the dog lung with constant flow. When the lobar venous outflow was occluded, the lobar venous pressure rose suddenly to a level somewhere below the arterial pressure, and then the arterial and venous pressures began to rise more slowly. A possible explanation for this response is that, when the outflow was occluded, flow through some downstream segment of the bed ceased. Because flow into the lung continued, the arteriovenous pressure difference after occlusion represents the pressure drop across some upstream segment through which the flow continued. We designated the arteriovenous pressure difference just after outflow occlusion as the upstream pressure drop. The arteriovenous pressure difference before occlusion minus the upstream pressure drop was designated the downstream pressure drop. In an attempt to better understand the meaning of the upstream and downstream pressure drops, we examined the influence of pulmonary vasoconstriction and flow direction on the size of the upstream and downstream pressure drops. We also compared these pressure drops with the pressure drops occurring upstream and downstream from the midpoint of the lobar vascular volume, using the low-viscosity bolus technique. The results indicate that changes in the upstream and downstream pressure drops, as evaluated by outflow occlusion, reflect changes in the lobar arterial and venous resistances.